Ethan Thompson and Jarod Lucas both scored 13 points, and Oregon State rode a stifling defensive effort to snap USC's six-game winning streak, 58-56, Tuesday at Gill Coliseum in Corvallis, Oregon.
The Beavers (7-5, 3-3 Pac-12 Conference) held the Trojans to 41.7 percent shooting from the floor and won the turnover battle, committing just eight turnovers against 13 by USC.
Oregon State held USC leading scorer Evan Mobley to 12 just points behind a game plan of persistent double-teams and traps each time he caught the ball.
Mobley grabbed a game-high 13 rebounds, while his brother, Isaiah Mobley, pulled down eight to pace USC's 35-28 advantage on the glass.
The Trojans (11-3, 5-2) complemented their rebounding edge with stout defense of their own, holding Oregon State to an identical 41.7 percent shooting percentage. The Beavers' 12-of-14 shooting from the free-throw line compared to the Trojans' 10-of-18 output proved critical.
USC started strong, scoring the game's first eight points. The Trojans missed all nine of their 3-point attempts in the first half, however, contributing to their overall shooting woes.
The Trojans went 9 of 25 from the floor and 5 of 10 at the free-throw line before intermission. USC going cold allowed Oregon State flip the deficit from down eight in the early minutes, to up eight at halftime.
The Beavers never trailed in the second half, but never led by more than eight points. Leading scorers Thompson and Lucas shot a combined 8-for-19 overall from the floor, while center Roman Silva shot 6-for-7 to contribute 12 points.
USC chipped away at the deficit throughout the second half, forcing two ties in the waning minutes.
Ethan Anderson scored three of his five points on a game-tying jumper off of an Evan Mobley feed, then found Evan Mobley on an interior pass for a dunk to knot the score at 56.
Isaiah Mobley was called for a foul on the ensuing possession. Rodrigue Andela's free throws proved to be the game-winner points, as both teams went scoreless for the final 1:49.
Anderson was called for an offensive foul driving down the lane on a late USC possession. Drew Peterson -- who scored 10 points -- caught a pass at the top of the key with a clean look at the rim, but after a pump fake, missed the would-be game-winning 3-pointer.
--Field Level Media